Liquid level gauge



J. F. WERDER 2,370,099

LI QUID LEVEL GAUGE Feb. 20, 1945.

Filed Feb. 3, 1944 INVENTOR. John F Werde-1^ TTX Patented Feb. 20, 1945 UNITED STATES PATENT OFFICE LIQUID LEVEL GAUGE John F. Werder', chagrin raus, oni Application February 3, 1944;, Serial Nor 520,975

(CL 7S-313) 3 Claims.

My invention relates to liquid level gauges and relates more particularly to a feature of improvement applicable to many types of liquid level gauges which depends upon the position of'a float element immersed in the liquid to control, by its position of elevationr the operation of a gauge instrument disposed at a distance from said float At the present time, liquid level gauges com monly employ a iioat to control the adiustment of an adjustablel primary controller mounted on the tank, or other receptacle containingr liquid, for controlling the operation of a remotely disposed gauge either through a fluid pressure line or electrical circuit conductors interconnecting said gauge and primary controller. Y

In -many cases, efforts have been made to employ float controlled remotely disposed indicator systems to indicate the level of lubricant in the crank case of an internal combustion engine employed in automobiles or involving like conditions of accumulated sludge which commonly settles towards the bottom of the crank case but which is variously dispersed to other portions of the liquid from time to time.

I have found that in many instances the indicati-ons remotely effected by the position ofthe float have been so highly unreliable that the use of such a oat in automotive engine crank cases has, in recent years, ybeen largely discontinued.

This, for the reason that the float tends to ."stick"y at various float levels which may not at all coineide, with the amount of lubricant including such sludge in the crank caser Instances have been known where, due to the effect of such sludge, the oat will stick in the "up" position thereby giving a remote indication of full, although as a matter of fact, the supply of lubricant in the crank case has been seriously depleted with consequent damage to the engine, engine cylinders and bearings. Y

Again, occasionally when the vehicle is not in perfectly horizontal position "fore-and-atf or laterally, the hinging connection between the dications given by the remotely disposed indicator.

By virtue ofthe apparatus herein disclosed, means are provided whereby the operatorL may, at any time, forcibly depress the float .below the oil level and maintain it in such lowered position, meanwhile noting any diiference, and the degree thereof, in the indication of oil level given yby the indicator. y

If the indicator then gives a substantially lower oil level reading, the operator will then release the float and note whether or not the re-` sultant increased oil level indication corresponds with that previously given before lowering of the iioat.

A few successive operationsy such as that above given will indicate to the operator the true ol level or, on the contrary, in the case of successive readings of varying value, will indicate that the apparatus is not operating correctly and will cause the operator to be put upon inquiry as to whether the sludge `should be removed from the crank case, new oil placed therein', or the mechanical or electrical mechanism is at fault.

Such an operation provides ample warning to the operatoras to any inaccuracies whereby the operator may eliminate the cause thereof beforel damage has been done to the engine. Even though the lubricating oil is free of sediment and` the apparatus and electrical system is in reasonably good working order, the depression of the oat being followed by release thereof, per- -mits the float to surge upwardly and momentarily slightly above its float level from which it then float supporting arm and the apparatus of the controller tends to bind. Particularly is this true where the ioat arm of the float is carredon .an arm extending laterally of the controller, for, the float sometimes is immersed to a greater orlesser extent in the body of the liquid, upon the surface of which it is intended to freely ride 'in order to achieve accurate indicator controlling results.

My present invention provides a means whereby the operator of the automotive vehicle or engine may readily, at any time, check the operativeness and reliability -of the float induced insettles on the surface ofthe yliquid at the proper indicating level whereby a more precise indication is often secured' than otherwise, especially when the test is made with a cold engine and the vehicle and engine are notin operation, the above achieving the common beneficial effects of vibration ,achieved when the enginev is in operation and/or the vehicle in motion not over.-

coming slight frictional effects related to the float or mechanical connections thereto.

It is an object therefor of my invention to provide an improved ancillary float controlling means operable whenever a reading ofthe gauge orindicator is to be made and fro-inthe point of observation of the indicator to ensure that the remotely controlled indicating apparatus not only is in proper Working order but that the float' is freely and properly responsive to the level of the liquid and is not stuck at some other than the proper float level at the surface of the4 liquid. Another object of my invention is to provide Another object of my invention is to provide an improved ancillary iioat controlling means operable whenever a reading of the gauge or indicator is to be made and from the point of observation of the indicator to ensure that the fioat is always pre-positioned accurately at the same level with respect to the surface of the liquid. l

Other objects of my invention and the invention itself will become more increasingly apparent from the purview of the description and the drawing attached hereto, in which:

The single figure shown is an illustration of the telemetric float controlling means of my invention showing in solid lines the normal position of the iioat, and in dotted lines several operative positions of the float as effected by the controlling means.

The drawing illustrates an embodiment of my invention applied to an oil level indicating system for purposes of illustrating an application of my invention, the illustrated system being ,that disclosed in United States Letters Patent No. 1,885,051 dated October 25, 1932, to T. J. Smulski.

Briey describing the liquid level electrical indicating system of the drawing, at I I show an indicator having a graduated scale and indicating hand of the usual type, the movement of the hand being electro-thermally accomplished in a manner well known and disclosed in said patent.

The so-called sender tube 2 comprises a pair of electrical contacts in normally closed circuit relation and maintained in variable pressure contact, the degree of pressure between the contacts being automatically adjustable by variations in the elevation of the plunger 3 which, v

in turn, is elevated to a degree depending upon the elevation of the float 4 disposed within the liquid container 5, which may be the gasoline tank of an automobile. 'l

The float 4 is commonly made of cork or other light material of low specific gravity and isgenerally indicated at 6. The float 4 is carried on an arm 1, pivoted at 8, in the member 9 which is secured to and extends downwardly of the casing of the sender 2. In the region generally indicated at I Il, the upper surface of the float arm 'I is generally of camming contour and the lower end of the plunger 3 rides upon the cam surfaces I0, being maintained in slight pressure contact therewith by the helical spring I l Itis sufficientrfor the purpose of the present application, which is not directed to the liquid level indicating system, per se, to add merely that the position of the needle of the indicator I is, at all times, during operation of the system responsive to the elevation of the plunger 3 underthe control of the cam portion I0 of the float arm 1.

The apparatus of my invention as applied to the indicating system ensures not only the float mechanism but also the remotely controlled indicating system and apparatus therefor being in proper working order, and said apparatus comprises a solenoid I2 and an armature plunger I3', the plunger being interlinked with a second arm I4 of the float arm element I but preferably extending in an opposite direction. The connection between the arm I4 and the plunger rod I 3 is preferably accomplished by providing the arm I4 with an elongated slot I5 into which a pin IS, carried by the plunger rod, projects. The push button circuit closure I6, disposed preferably adjacent the indicator I, is separately carried by the instrument board or, if preferred, mayv be incorporated into the instrument I, if desired.

When the float gauge system is, as in the embodiment illustrated, electrically operated, the

source of current B is, when the ignition switch shown at I is operated to turn on the ignition of the automobile, connected through the supplemental switch contacts I8 and I9 to both the gauge electrical indicating system and the solenoid I2. This is accomplished by virtue of the fact that the vsupplemental blade 2D bridges the contacts I8 and I9 and interconnects the ungrounded pole of the battery B through said contacts through a Contact 2| of the push button switch I6 to the circuit conductor 22 leading to the indicator I.

Therefore, with the switch I thrown to closed position, as when the ignition switch of the automobile is closed, current Will flow from the battery B through the contacts of switch I and then serially through the circuit conductor 22, the indicator I, the circuit conductor 23 to the sender 2 which commonly is grounded, or if not, may be grounded, through the circuit conductor 24. At the same time, the supplemental circuit for the solenoid I2 is conditioned for operation by the closure of the contacts I8 and I9. t will be understood that in the operation of the solenoid, the operator, having first operated the ignition switch I, will note the reading of the indicator I, and then, before relying mon the indication then given by the indicator I, will operate the push button switch I6 to effect energization of the solenoid I2. Responsive to such energization, the armature plunger I3 and plunger rod I3 will be drawn upwardly within the solenoid and therefore, by virtue of the slot and pin connection I5 and IB with the float arm l, will forcibly depress the float from some such position as indicated at e to the dotted line posi# tion y.

Meanwhile, maintaining the push button switch I6 2I in closed circuit position, the operator will note the consequent lowered position of the indicator needle which should properly take a definite position known to the operator by experience and the operator will thus be able to check the accuracy of the remotely controlled electrical system for such lower float level y, Subsequent releasing of the push button switch to open the contacts thereof may permit the float 4 to be displaced upwardly by the effect of buoyancy and the force of buoyancy may be suf'liciently strong to mom-entarily cause the float to assume a slightly more elevated position, from which position the oat will gently settle upon the surface of the liquid to take the intermediate proper position 'as shown at e.

The above operation is the normal and eX- pected operation. However, if the crank case oil has been so contaminated by sediment, sludge or the like, or if the mechanical connections between the float arm 'I and the sender appa ratus 2 bind, due to friction or for any other reason, the operator will be able to detect each difficulty by the varying erratic different indications given by the indicator upon successive operations of the push button and by comparison also with the previously experienced indications given when the float is at the position y. In such case, the operator being putupon inquiry will not rely upon the indicating system and will seek the cause of the inaccuracies and remedy the same, usually by replacing the contaminated oil with clean oil.

While the drawing and the foregoing specification illustrate an electrical liquid level indieating system and apparatus therefor, and electro-magnetic actuating means for effecting a preliminary downward movement of the flow to ensure a more accurate indication of liquid level, it will be clear that my invention may be applied to any other oat-actuated mechanism or system, since the operation of the apparatus of my invention is not dependent upon any particular means or method for translating movements of the float to an extraneously disposed indicator.

The indicator, at l, may be of any desired form and its actuation may, ,for instance, be effected mechanically through a flexible wire or otherwise, as well known in the art. I consider such within the broad purview of my invention, independently of the nature of the indicating ap paratus which is variably operated responsive to the position of the iloat in the liquid.

From the foregoing, other alternative embdiments of my invention and the broader scope thereof will be'known and appreciated by those skilled in the art and I am aware that numerous and extensive departures may made from the embodiment herein illustrated and described, without however departing from the spirit of my invention and the scope of the appended claims.

I claim:

1. In combination with a liquid containing receptacle, a float controlled liquid level indicator, a controller carried on the receptacle, said indicator disposed at an operators station remotely of said receptacle, a float arm pivoted for swinging oscillatory4 movement in, or nearly in, a vertical plane, a float carried by said arm, said indicator being responsive to varying elevations of said float to indicate the degree of elevation thereof, electro-magnetic means carried by the receptacle adapted when energized to momentarily swing said arm downward ly to depress said float to a substantially lower known level, an electrical switch and a source of current, and electrical circuit conductors interconnecting said switch, said source and ysaid electro-magnetic means whereby when said switch is closed the electromagnetic means will depress the float, and upon opening the switch the float will return to the liquid level surface whereby the operator may compare the indicator reading prior to any depressing actuation of said float to any subsequent reading taken after the iloat is restored to the surface of the liquid to detect faulty indicating positioning of said' float. i

2. In combination with a oat actuated liquid level indicating system, electrical means for arbitrarily positioningr the float thereof, comprising an electro-magnetic device provided with an armature, means interlinking the armature of said device and said oat to depress the float substantially below the level ofthe liquid when the magnet of said device is energized, and a source of current, a switch, and electrical circuit conductors, said conductors and switch,

being adapted to interconnect said source with the winding of said device, whereby the accuracy of the indicating system and mechanism 'may be checked at a, denite low level position of said oat and whereby indicator readings may be taken prior to and after any actuation of said electro-magnetic device.

3. In combination with the crank case of an internal combustion engine with a oat within said crank case, a remotely disposed liquid level indicator means, electrical telemetric means variably operated by said float according to the elevation thereof for correspondingly varying the indication given by said indicator, electromagnetic means comprising an electromagnet having an armature, and means interconnecting said armature and said float, a source of current, an electrical circuit controller and electrical circuit conductors interconnecting said controller, said electromagnet and said source, said controller being positioned in the vicinity of said indicator and adapted to force said oat to a known lower elevation than the variable eleva.- tion thereof when disposed at the surface of the variable amount of lubricant inthe crank case, whereby the operator may check the accuracy of said telemetric means by operation of said manual float depressing means and whereby the operator may by repeated sequential. operations y of said manual means compare the indications of said indicator at different times when said manual means is inoperative to depress the iioat and subsequent to depression of said float, and whereby upon manual disabling of said controller, said oat will be restored to normal floating position at the surface of the lubricant, the manually controlled movement thereof being effective to dislodge sludge from said oat.

JOHN F. WERDER. 

